1. Field of the Invention
The present invention relates generally to Universal Plug and Play (UPnP), and more particularly, to a method for exchanging information between two devices in real-time in UPnP.
2. Description of the Related Art
Generally, a home network is a private network based on Internet Protocol (IP), and connects any type of a Personal Computer (PC) used at home and various devices, such as intelligent products, wireless devices, and the like, to one network, and controls that network via a common virtual computing environment called middleware.
Middleware enables communication between various digital devices by connecting the digital devices by using a peer-to-peer method. Examples of middleware include Home AV Interoperability (HAVI), a Universal Plug and Play (UPnP) control device, a Java Intelligent Network Infrastructure (JINI), a Home Wide Web (HWW), and so forth.
In a computing environment established through the UPnP middleware, each device is allocated an address according to the Dynamic Host Configuration Protocol (DHCP), or is allocated an address selected by the Automatic IP-specifying function (Auto IP), through which communication is performed.
The UPnP network is a home-network technology, which defines the UPnP device and the UPnP service, and is defined by the protocol between them. The UPnP network is constituted by a Controlled Device (CD), which is a home-network device connected to and controlled by the home network, and a Control Point (CP), which is a device for controlling such a CD. The CP controls the CD, and requests and receives events. The CD performs specified functions according to the request of the CP, and when the state of the CD is changed, the CD sends the event to the CP that has requested the event.
Smart grid technology, provides integration technology into an existing home network power net to allow a power provider and a consumer to exchange real-time information interactively. The smart grid is a next-generation functional grid, which optimizes energy efficiency because the power provider and the consumer interactively communicate with one another by using the existing grid.
Currently, as a leader of standard technologies of in-home smart grid, the Zigbee® Smart Energy Profile (SEP) 2.0 technology is used. The Zigbee® SEP 2.0 technology is a lightweight profile based on REpresentational State Transfer (REST), and operates on the HyperText Transfer Protocol (HTTP). The Zigbee® SEP 2.0 technology defines a data model, a REST-based Uniform Resource Identifier (URI), a device type, a function set, and the like.
However, in the current UPnP network, a technique for interactively exchanging real-time information by using an existing grid as in the smart grid is not applied. Therefore, there is a need for a technique for exchanging information on a real-time basis by using an existing UPnP network grid.